Living outside the law they are the anti government extremists next door who believe the laws don't apply to them. No driver's licenses no taxes at according to report out today these types of so called hater anti government groups. Grew explosively. Last year in the US one of the biggest jumps seemingly average people who call themselves sovereign citizens. A loose confederation of Americans who can turn violent. And half. Here's ABC's Dan Harris with tonight's Nightline investigates. The federal government considers them -- quote extremist anti government group. That -- I hereby challenge -- -- -- fiction as a result and I am not American citizen I do not recognize them as president flag. Elliott by Dallas home with a sovereign citizens people who believe the laws of America do not apply to them. They have their own driver's licenses they have their own hunting licenses they have their own business -- Violence has gotten this is a lot of attention that these incidents are really just. -- -- -- -- -- -- Snide -- border area. This -- and -- -- estimated to be 100000 strong and growing in every state in America. Whose members argue they are really patriots. Defenders of freedom in a country -- increasingly tyrannical government. To find out if these people are motivated by love of liberty or as their critics say by greed anarchy and blood lust. Nightline went deep inside a notoriously -- Shiite movement we started here at a diner outside Tampa Florida -- everybody. Undergone the first impression was striking these are not what many of us would expect anti government extremists to look like. They're -- middle class educated. And convinced that the government is out of control. We put cover me and I beg borrow or rent but he tied up to expedite the problem right and a -- man -- -- -- that was -- -- almost certainly isn't. Yeah. How -- them most insisted. They are nonviolent. But not all of them ruled it out president of the -- you know what -- you come here with a bull crap about trying to impress -- do. Pres ABC news about how -- I don't give a crap how many -- they. Two OK well about. Next we found ourselves at this small church in center point Alabama. Donald Joseph barber -- pastor here. Invited us inside for a rare look at a meeting with his congregation of -- In -- view. Do you need to have a -- you know. He native -- but now. What about taxes income tax -- -- -- income tax because. Live in the United States. Where you live. Some. You're describing as a domestic terrorist and hitting any agency can come and rescue for domestic -- they can -- you want some polling place and you die. Under the law so the way you discredit this government is totally -- absolute look. You think we're living in a police they -- -- What do you play except well late thank they have all the ration you have learned from the beginning. Barber who is a former photo copier salesman. And made himself into a scholar of sovereign ideology of bizarre -- together -- passages from obscure log books. Along with parts of the constitution and the Bible. All to justify -- flouting the law. People all over the country are now using sovereign theories to justify failure to repay their debts and even to occupy foreclosed homes. And when police prosecutors and judges stand in the way of a sovereign like Donald barber. They often resort to a classic sovereign weapon called Paper terrorism. Flooding officials with paperwork. Donald -- demanded money from this -- it was a demand for four million dollars. And gold. Filed a fifteen million dollar lien against this judge. Were you angry. Owls went ballistic of course -- -- And -- sent a letter to this police chief saying you better get out of dodge -- -- is good because a new sheriff is about to ride up on you. Your word maybe they are wanna follow through with -- all counts as a kidnapping threat or are they gonna come after your friendly and Benjamin Franklin's stated that. This should be a revolution every twenty years. It was a long time passed -- do you thing we need a revolution now. I think -- the revolutions but not a violent one. Sovereign citizens do have a history of turning violent. Terry Nichols cold water of the Oklahoma City bombing bus every citizen. Joseph stack who flew his small plane into an IRS building in Austin, Texas. A sovereign citizen. And then there's Jerry Ngo -- father and his sixteen year old son -- -- used to drive around the country teaching people how to use sovereign legal theories to get out of debt. I don't want to kill them. But if they see that's that's worth well. When they were pulled over in West Memphis, Arkansas and 2010. Joseph -- burst out of the car when an assault rifle and killed two officers. God wouldn't be -- -- later cornered and shot to death in the parking lot of a Wal-Mart. Apollo -- over my radio this as an officer down. And says two officers them. Police chief Bob powder rushed to deceit so I don't run up that he'll and one must start stop me and says -- please don't go up there. Well under the and they had to be Brandon. -- -- the chief's son and fellow officer was dead it was the most horrific day of my life I've never experienced -- time playing like that. Did you ever heard of seven citizens before. Had never heard to turn sovereign citizens OK we got sovereigns were we don't do. Now Bob powder travels the country teaching local law enforcement officials. About sovereign citizen. On our journey we found two irreconcilable. Views of this movement. Donald -- -- about to go on trial for allegedly threatening government officials and facing decades in prison. -- -- -- -- -- -- Just as a soldier goes over to a reactor to Iran or any other country to fight a battle is gone over because he loves his country. I can't do any less. But for Bob powder who lost his son sovereign citizens are domestic terrorists. Who must be stopped. The plane is still there will always be there. But it certainly gives me satisfaction knowing. That probably worth saving lives that some other found they won't have to go this for Nightline this is Dan Harris in Tampa Florida.

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